A system for measuring a living subject having a spine comprises a flexible strip, a first sensor, a processor, and a data storage device. The flexible strip, the first sensor, the processor, and the data storage device are located along the spine of the living subject. The first sensor, the processor and the data storage device are connected for collecting data related to bending of the flexible strip for determining a curvature of the spine of the living subject. The data from the first sensor is processed in the processor and stored in the storage device. One embodiment includes a transmitter for transmitting the data. Other embodiments include feedback and provide information about time duration in a posture.